Originally Posted by
Mr IGH
Triple and a little gearfreaking allows me a wide range of gears with small steps. Works well for me on those 10 mile climbs, averaging 7%, topping out over 11,000ft. I hate to walk and I can't stand on the pedals whilst climbing as I did in my younger days.
I run a Tiagra 4503 52/39/24 triple on my road bike with a 14-28 nine speed cassette. When it was time to select the drive train for my new build, I found an older Shimano 105 5703 crankset 30/39/50 then configured it 24/39/53 with the same 14~28 nine speed cassette.
I see Shimano is still selling the 5703, my favorite road triple because the inner ring is 74mm for a minimum 24T inner ring. The newer Tiagra/Sora triples have a bastard BCD on the inner ring that forces a 30T minimum, not small enough for my tastes.
Since the 39T is a 10-speed ring, I get better shifting from this setup by replacing the 52 with a 53T type B ring, which is meant to be used with the 39T. The 52 is designed for a 42 middle ring.